Event related potentials (ERP) were chosen as the main tool for this non-invasive approach to motivational (emotional) processes in the human brain. Other methods, such as NIRS or fMRI may be included at a later stage. ERP are scalp potentials, derived from the EEG (Electro-Encephalo-Graph) by averaging time-locked activity in response to a stimulus. The significant advantage of the EEG for functional imaging is its time resolution, in the order of milliseconds. This is the time scale in which cognitive (and emotional) processes take place. Human EEG was first recorded by Hans Berger, in 1925. Evoked potentials have been used in neuroscience and in clinics for over 40 years. Its high temporal resolution (in the order of milliseconds) in addition to its availability in measuring brain activity in healthy people (the method is non invasive), make it very suitable to measure neural activity associated with cognitive and emotional processes in humans.